Fire officials responded to the two-story wood-frame house on Saratoga Street just before 8 a.m. and found a man on fire in a bed in the basement. The district chief said the fire was not smoking-related.

Investigators said it appeared the victim’s hands were tied.

“When they made entry, naturally under the smoke conditions, visibility was poor, and they felt a body in the mattress. At that time, they attempted to pull the body and get he or she out, and that’s when I saw they had a non-viable patient,” said Chief Stephen Paschal of the Boston Fire Department.

WBZ-TV’s Bill Shields reports.

One firefighter was taken to Mass. General Hospital with a back injury.

Fire officials and Boston Police Homicide Detectives are investigating. Police are looking into the possibility that Flores was living in an illegal apartment.

The last fatal fire in Boston was on May 29, 2010 in East Boston, according to the Boston Fire Department.